The goal of the PI's undergraduate-based research program is to understand the cellular mechanisms and underlying genetic basis of pronephric duct (PD) extension in amphibian embryos. In all vertebrate embryos, PD primordia must extend from the pronephros to the cloaca in order to form the functional conduit for excretory waste. PD tissue is also required to induce terminal differentiation of larval and adult kidney forms; if PD tissue does not appear in the nephrogenic mesenchyme in the right place at the right time, kidney agenesis results. Although PD extension appears superficially similar in all vertebrates, careful analysis reveals that the cellular basis of PD elongation is different in different animals. The studies proposed here will use tissue extirpation, transplantation and fate-mapping to compare PD extension in Xenopus laevis and Ambystoma mexicanum embryos with a focus on understanding the Xenopus system as well as we do Ambystoma. In addition, molecular analysis of the Ret protein tyrosine kinase signaling system, known to be important for PD cell migration in Ambystoma, will be initiated in Xenopus laevis embryos.
Intellectual merit: Despite the fact that PD elongation is the central event in establishing the vertebrate excretory system, little is known about the cell and tissue behaviors that lead to its morphogenesis. However, understanding these behaviors is essential to the informed interpretation of molecular studies. Therefore, the experiments proposed here will help provide a phenomenological context for the growing number of genetic studies of pronephric system development in amphibians, as well as provide a comparative basis for studies of PD extension in other vertebrate groups. Thus, the proposed studies will provide the developmental biology community with fundamental information about excretory system development and evolution.
Broader impacts: The proposed activities will be conducted by the PI and undergraduates at Rider University. Rider's student demographic includes 19% underrepresented minorities, 25% first-generation college students and 60% women. Thus, the PI's research program benefits several groups typically underrepresented in science careers. Furthermore, most of the students performing independent research in her lab have the opportunity to present their work at regional or national scientific meetings. All graduates from her laboratory have pursued science-related careers. The PI's synergistic activities include K-12 science education outreach and curriculum development. In sum, the broader impact of the PI's professional activities include the advancement of discovery while promoting teaching, training and learning; broadening the participation of underrepresented groups; and, through integration of her research into her undergraduate courses and expanding her undergraduate audience to include K-12 education majors, broad dissemination to enhance scientific and technological understanding.
